This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Polymavirus is latent in the kidney of up to 50% of healthy adults. In kidney transplant patients maintained on immunosuppressive drugs, reactivation of virus can result in polymovirus allograft nephropathy (PVAN). PVAN is an inadequately studied and distressing condidtion that frequently leads to graft loss. The study being proposed explores the notion that changes in viral genomic structure might play an important role in the initiation and subsequent progression of this disease